A crew member on the International Space Station (ISS) took this photo in May 2022 while in orbit more than 400 kilometers (250 miles) above Earth’s surface. At the time, the ISS was over the South Pacific Ocean about 500 kilometers (300 miles) southwest of Tahiti. Only a small amount of ocean is visible in this photo. Instead, the side view shows the edge of the Earth — and layer upon layer of the atmosphere. Clouds float in the troposphere, the layer closest to the planet’s surface. Higher up in the stratosphere and mesosphere, the sky darkens as there are fewer particles around to scatter the light. In the background, the waning moon shines like a beacon through the thinnest layers of Earth’s atmosphere. This rocky companion of Earth is the focus of NASA’s Artemis missions, which will return astronauts to the Moon while testing tools and ideas for human missions to Mars. A key purpose of the uncrewed Artemis I mission is to ensure that the crew module can safely perform its entry and descent into the Earth’s atmosphere, as well as its disintegration and recovery. The next mission, Artemis II, will include a human crew. This pair of photos shows NASA’s Space Launch System (SLS) rocket, carrying the Orion spacecraft, during preparations for the launch of Artemis I. NASA photographer Keegan Barber took the first photo on August 29, 2022. The effort launch that day was canceled when the engines in the rocket’s core stage were unable to meet the appropriate temperature range. NASA photographer Bill Ingalls took the second sunrise photo while launch preparations continued on August 31, 2022. The next launch attempt was targeted for September 3. In both photos, the launch site is framed by distinct features of our atmosphere. For example, looming clouds speak of the abundant warmth and humid air in Florida in the summer, when thunderstorms are an almost daily occurrence. (As of August 31, sporadic showers were predicted around the afternoon launch window of September 3.) In the sunrise photo, the low horizon appears red because more blue light is scattered when sunlight must travel to our eyes through more gases and particles in the atmosphere. In contrast, the Moon has no atmosphere, at least not in the sense that Earth does. Instead, the Moon has a very thin, thin layer of non-breathable gases known as the exosphere. For the past five decades, astronauts have lived and worked in orbit around Earth, taking millions of pictures of their planet. In due time, they will observe their home again from 240,000 miles of space. Astronaut photo ISS067-E-70919 was acquired on May 21, 2022, with a Nikon D5 digital camera using a 420mm lens and provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at NASA/JSC’s Gateway to Astronaut Photography of Earth. Photos by NASA/Keegan Barber and NASA/Bill Ingalls. Story by Kathryn Hansen.
